Compared with general multifunctional moiety-type acrylic monomers such as pentaerythritol triacrylate and dipentaerythritol hexaacrylate, the acrylic-modified melamine resins had the same degree of hardness. In addition, flexibility, a feature of the urethane moiety, was imparted to the polymer by the reaction of residual hydroxyl groups with isocyanate. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123: 307-315, 2012″
“Two kinds of junctions based on doped graphene nanoribbons (GNRs) are designed and studied in this article. One is the N-doped armchair GNR (AGNR) joined directly by B-doped AGNRs, and another is similar,

but there is an undoped AGNR between them. The transport properties are calculated using the full self-consistent ab initio nonequilibrium Green’s function SB203580 supplier and density-functional SNX-5422 in vivo theory methods under external bias. We find that the I-V curves for both junctions have a striking nonlinear feature and show large negative differential resistance properties, not only at the positive bias but also at the negative one. The results also indicate that the diode-like properties are kept and the rectification coefficient

is very high within a wide bias region. Our calculations reveal that the formation of these peculiar transport behaviors is due to the great changes of the transmission spectra and the projected self-consistent Hamiltonian eigenvalues with the applied

bias voltage. These findings suggest that the doped AGNRs may offer unique opportunities for the future development of nanoscale electronics. (C) 2011 American Institute of Physics. [doi:10.1063/1.3605489]“
“The effects of an intercalating agent on the morphology and thermal and flame-retardant properties of low-density polyethylene (LDPE)/layered double hydroxide (LDH) nanocomposites were studied with Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, microscale combustion calorimetry, thermogravimetric analysis, and mechanical property measurements. X-ray diffraction and transmission Selleckchem VX-680 electron microscopy demonstrated that after intercalation with stearate anion (SA) or dodecyl sulfate anion (DS), organo-LDH could be nanodispersed in an LDPE matrix with exfoliated structures or intercalated structures simultaneously with partially exfoliated structures, respectively, via melt intercalation. However, the unmodified LDH composites yielded only microcomposites. Microscale combustion calorimetry, thermogravimetric analysis, and dynamic Fourier transform infrared spectra showed the following order for the flame-retardant and thermal properties: LDPE/SA-modified LDH > LDPE/DS-modified LDH > LDPE/NO(3)-modified LDH > LDPE.